Our intuition tells us that a giant planet like Jupiter - standing at 11 times the diameter of Earth and more than 300 times its mass - should spin far more slowly than Earth. But the opposite is true: a Jupiter day is only 9.9 Earth hours. That rapid spin is a remnant of Jupiter’s formation long ago. When a newly-forming planet gathers up gaseous material, it gravitationally contracts as it slowly spins in some net direction. As this material falls inward, its spin rate increases due to conservation of angular momentum, much like a twirling figure skater spins faster as she pulls her arms inward. The giant planets, like Jupiter and Saturn, retained a lot more of this angular momentum than the terrestrial planets, like Earth and Mars, which were more influenced by heavy impacts. Jupiter is not a solid sphere, like the terrestrial planets, but is essentially a giant ball of gas, like the much larger Sun. So, Jupiter rotates differentially, just like the Sun, spinning fastest near its equator and slower near its poles. Measurements of Jupiter’s magnetic field tell us its interior - where layers of metallic hydrogen may surround a slushy rock/ice core - rotates more rigidly and a little more slowly than its surface. Majestic Jupiter is one of my favorite planets. The ancient Romans were equally impressed with it. They saw this bright wandering object in the sky and named it after their chief god - the “sky father.” But this chief of the planets was made by the true Father of the sky, who is infinitely greater than any god or object in the universe. As David wrote in Psalm 19, “The heavens declare the glory of God, and the skies proclaim the work of his hands.”